Annuloplasty ring with reduced dehiscence

ABSTRACT

A prosthetic remodeling annuloplasty ring for use in tricuspid or mitral valve repairs to provide support after annuloplasty surgery. The annuloplasty ring includes a relatively rigid core extending around an axis that is discontinuous to define two free ends. A suture-permeable interface surrounding the core includes floppy regions adjacent both free ends of the core. Sutures are used to attach the annuloplasty ring to the annulus, including at least one suture through each of the floppy regions to secure the free ends of the ring and minimize the risk of ring dehiscence, or pull through of the sutures through the annulus tissue. The floppy regions may project from each free end into the gap toward each other, be radially enlarged such as paddle-like extensions, or may comprise outwardly lateral extensions at the free ends of the core.

CROSS REFERENCE TO RELATED APPLICATIONS

This application is a continuation of U.S. application Ser. No.14/595,075, filed Jan. 12, 2015, now U.S. Pat. No. 9,474,607, which is adivisional of U.S. application Ser. No. 13/305,546, filed Nov. 28, 2011,now U.S. Pat. No. 8,932,350, which claims the benefit of U.S.Application No. 61/418,190, filed Nov. 30, 2010, the entire disclosuresof which are incorporated by reference herein.

FIELD OF THE INVENTION

The present invention relates generally to methods of implanting medicaldevices in particular annuloplasty rings with reduced propensity fordehiscence.

BACKGROUND OF THE INVENTION

In vertebrate animals, the heart is a hollow muscular organ having fourpumping chambers: the left and right atria and the left and rightventricles, each provided with its own one-way valve. The natural heartvalves are identified as the aortic, mitral (or bicuspid), tricuspid andpulmonary, and are each mounted in an annulus comprising dense fibrousrings attached either directly or indirectly to the atrial andventricular muscle fibers. Each annulus defines a flow orifice.

Valve disease can be severely debilitating and even fatal if leftuntreated. Various surgical techniques may be used to repair a diseasedor damaged valve. Repair or reconstruction, as opposed to valvereplacement, is typically used on minimally calcified valves. One repairtechnique that has been shown to be effective in treating incompetenceis annuloplasty, in which the deformed valve annulus is reshaped byattaching a prosthetic annuloplasty repair segment or ring to the valveannulus. The annuloplasty ring is designed to support the functionalchanges that occur during the cardiac cycle: maintaining coaptation andvalve integrity to prevent reverse flow while permitting goodhemodynamics during forward flow.

The annuloplasty ring typically comprises an inner substrate of a metalsuch as rods or bands of stainless steel or titanium, or a flexiblematerial such as silicone rubber or Dacron cordage, covered with abiocompatible fabric or cloth to allow the ring to be sutured to thefibrous annulus tissue. Annuloplasty rings may be stiff (e.g., titanium)or flexible (e.g., silicone), though a “remodeling” annuloplasty ringtypically has an inner core that resists conforming to the nativeannulus shape and instead forces the annulus to conform to it. Rings mayhave a continuous periphery (e.g., D-shaped) or a discontinuousperiphery with a gap between free ends (e.g., C-shaped). Examples areseen in U.S. Pat. Nos. 5,041,130, 5,104,407, 5,201,880, 5,258,021,5,607,471 and 6,187,040. Most annuloplasty rings are formed in a plane,with some D-shaped mitral rings being bowed along their straight side toconform to the shape of the annulus at that location. Newer ringsinclude a variety of three-dimensional shapes to correct particularanatomical pathologies; such as U.S. Pat. Nos. 6,805,710, 7,367,991, and7,608,103.

Whether totally flexible, rigid, or semi-rigid, annuloplasty rings havebeen associated with a 10% to 15% ring dehiscence incidence at 10 years,thus requiring a reoperation. The present invention is intended toreduce this complication.

For the purposes of anatomic orientation, please refer to FIG. 1, whichis a schematic representation of the atrioventricular (AV) junctionswithin the heart and the body in the left anterior oblique projection.The body is viewed in the upright position and has 3 orthogonal axes:superior-inferior, posterior-anterior, and right-left (lateral).

FIG. 2 is a cutaway view of the heart from the front, or anterior,perspective, with most of the primary structures marked. As is wellknown, the pathway of blood in the heart is from the right atrium to theright ventricle through the tricuspid valve, to and from the lungs, andfrom the left atrium to the left ventricle through the mitral valve. Thepresent application has particular relevance to the repair of thetricuspid valve, which regulates blood flow between the right atrium andright ventricle, although certain aspects may apply to repair of otherof the heart valves. The tricuspid and mitral valves together define theAV junctions.

As seen in FIG. 2, four structures embedded in the wall of the heartconduct impulses through the cardiac muscle to cause first the atriathen the ventricles to contract. These structures are the sinoatrialnode (SA node), the atrioventricular node (AV node), the bundle of His,and the Purkinje fibers. On the rear wall of the right atrium is abarely visible knot of tissue known as the sinoatrial, or SA node. Thistiny area is the control of the heart's pacemaker mechanism. Impulseconduction normally starts in the SA node which generates a briefelectrical impulse of low intensity approximately 72 times every minutein a resting adult. From this point the impulse spreads out over thesheets of tissue that make up the two atria, exciting the muscle fibersas it does so. This causes contraction of the two atria and therebythrusts the blood into the empty ventricles. The impulse quickly reachesanother small specialized knot of tissue known as the atrioventricular,or AV node, located between the atria and the ventricles. This nodedelays the impulse for about 0.07 seconds, which is exactly enough timeto allow the atria to complete their contractions. When the impulsesreach the AV node, they are relayed by way of the several bundles of Hisand Purkinje fibers to the ventricles, causing them to contract. Asthose of skill in the art are aware, the integrity and properfunctioning of the conductive system of the heart is critical for goodhealth.

FIG. 3 is a schematic view of the tricuspid valve orifice seen from itsinflow side (from the right atrium), with the peripheral landmarkslabeled as: antero septal commissure, anterior leaflet, antero posteriorcommissure, posterior leaflet, postero septal commissure, and septalleaflet. Contrary to traditional orientation nomenclature, the tricuspidvalve is nearly vertical, as reflected by these sector markings.

From the same viewpoint, the tricuspid valve 20 is shown surgicallyexposed in FIG. 4 with an annulus 22 and three leaflets 24 a, 24 b, 24 cextending inward into the flow orifice. Chordae tendineae 26 connect theleaflets to papillary muscles located in the right ventricle to controlthe movement of the leaflets. The tricuspid annulus 22 is anovoid-shaped fibrous ring at the base of the valve that is lessprominent than the mitral annulus, but larger in circumference.

Reflecting their true anatomic location, the three leaflets in FIG. 4are identified as septal 24 a, anterior 24 b, and posterior (or “mural”)24 c. The leaflets join together over three prominent zones ofapposition, and the peripheral intersections of these zones are usuallydescribed as commissures 28. The leaflets 24 are tethered at thecommissures 28 by the fan-shaped chordae tendineae 26 arising fromprominent papillary muscles originating in the right ventricle. Theseptal leaflet 24 a is the site of attachment to the fibrous trigone,the fibrous “skeletal” structure within the heart. The anterior leaflet24 b, largest of the 3 leaflets, often has notches. The posteriorleaflet 24 c, smallest of the 3 leaflets, usually is scalloped.

The ostium 30 of the right coronary sinus opens into the right atrium,and the tendon of Todaro 32 extends adjacent thereto. The AV node 34 andthe beginning of the bundle of His 36 are located in the supero-septalregion of the tricuspid valve circumference. The AV node 34 is situateddirectly on the right atrial side of the central fibrous body in themuscular portion of the AV septum, just superior and anterior to theostium 30 of the coronary sinus 30. Measuring approximately 1.0 mm×3.0mm×6.0 mm, the node is flat and generally oval shaped. The AV node 34 islocated at the apex of the triangle of Koch 38, which is formed by thetricuspid annulus 22, the ostium 30 of the coronary sinus, and thetendon of Todaro 32. The AV node 34 continues on to the bundle of His36, typically via a course inferior to the commissure 28 between theseptal 24 a and anterior 24 b leaflets of the tricuspid valve; however,the precise course of the bundle of His 36 in the vicinity of thetricuspid valve may vary. Moreover, the location of the bundle of His 36may not be readily apparent from a resected view of the right atriumbecause it lies beneath the annulus tissue.

The triangle of Koch 38 and tendon of Todaro 32 provide anatomiclandmarks during tricuspid valve repair procedures. A major factor toconsider during surgery is the proximity of the conduction system (AVnode 34 and bundle of His 36) to the septal leaflet 24 a. Of course,surgeons must avoid placing sutures too close to or within the AV node34. C-shaped rings are good choices for tricuspid valve repairs becausethey allow surgeons to position the break in the ring adjacent the AVnode 34, thus avoiding the need for suturing at that location.

One prior art rigid C-shaped ring of the prior art is theCarpentier-Edwards Classic® Tricuspid Annuloplasty Ring sold by EdwardsLifesciences Corporation of Irvine, Calif. Although not shown, theClassic® ring has an inner titanium core (not shown) covered by a layerof silicone and fabric. The Classic® ring is shaped and designed fordownsizing diseased annuluses with Rheumatic Fever damage. The surgeontypically attaches the Classic® ring to the tricuspid annulus usingsingle loop interrupted sutures along the outer edge of the ring.

Despite existing annuloplasty ring designs, there is a need for aprosthetic annuloplasty ring that has less propensity for dehiscence.

SUMMARY OF THE INVENTION

The present invention provides an annuloplasty ring including arelatively rigid inner core surrounded by a suture-impermeableinterface. The core is discontinuous with two free ends separated acrossthe gap, and the interface defines floppy regions adjacent each of thetwo free ends through which implant sutures are passed. Securing thefloppy regions to the valve annulus helps position the annuloplasty ringwhile reducing ring dehiscence. The floppy regions may be enlargedradially or circumferentially, and may resemble paddle-like appendagesor outwardly lateral wings.

A further understanding of the nature and advantages of the inventionwill become apparent by reference to the remaining portions of thespecification and drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

Features and advantages of the present invention will become appreciatedas the same become better understood with reference to thespecification, claims, and appended drawings wherein:

FIG. 1 is a schematic representation of the AV junctions within theheart and the body in the left anterior oblique projection;

FIG. 2 is a cutaway view of the heart from the front, or anterior,perspective;

FIG. 3 is a schematic plan view of the tricuspid annulus with typicalorientation directions noted as seen from the inflow side;

FIG. 4 is a plan view of the native tricuspid valve and surroundinganatomy from the inflow side;

FIG. 5 is a longitudinal sectional view of an exemplary annuloplastyring of the present application as seen from the atrial or inflow sideof the ring;

FIGS. 5A-5C are lateral sectional views through several locations of theannuloplasty ring of FIG. 5 taken along respective sectional lines;

FIG. 6 is a longitudinal sectional view of an alternative annuloplastyring of the present application as seen from the atrial or inflow sideof the ring;

FIGS. 6A-6C are lateral sectional views through several locations of theannuloplasty ring of FIG. 6 taken along respective sectional lines;

FIG. 7 is a longitudinal sectional view of an alternative annuloplastyring of the present application as seen from the atrial or inflow sideof the ring;

FIGS. 7A-7C are lateral sectional views through several locations of theannuloplasty ring of FIG. 7 taken along respective sectional lines;

FIG. 8 is a longitudinal sectional view of another annuloplasty ring ofthe present application as seen from the atrial or inflow side of thering;

FIGS. 8A-8C are lateral sectional views through several locations of theannuloplasty ring of FIG. 8 taken along respective sectional lines; and

FIG. 9 is a schematic illustration of an exemplary assembly of anannuloplasty ring and a securing plate for stabilizing free ends of theannuloplasty ring.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

The present invention provides an improved tricuspid annuloplasty ringthat better conforms to the native annulus and is configured to reducedehiscence, or pull-through of sutures from annulus tissue, especiallyat the free ends of the ring.

It should also be understood that certain features of the presenttricuspid ring might also be applicable and beneficial to rings forother of the heart's annuluses. For instance, the same structure mightbe used in a discontinuous ring for the mitral valve annulus.

The term “axis” in reference to the illustrated ring, and othernon-circular or non-planar rings, refers to a line generallyperpendicular to the ring that passes through the area centroid of thering when viewed in plan view. “Axial” or the direction of the “axis”can also be viewed as being parallel to the direction of blood flowwithin the valve orifice and thus within the ring when implantedtherein. Stated another way, the implanted tricuspid ring orients abouta central flow axis aligned along an average direction of blood flowthrough the tricuspid annulus. The rings of the present invention may be3-dimensional, though portions thereof may be planar and lieperpendicular to the flow axis.

With reference to FIG. 5, an exemplary annuloplasty ring 40 of thepresent application is shown in longitudinal sectional view from theinflow side of the ring. The term longitudinal sectional view refers toa section through the annuloplasty ring 40 that extends around theperiphery of the ring, but does not have to be in a single plane. Thatis, if the annuloplasty ring 40 exhibits three dimensions, in thatportions bow up or down out of a nominal plane, then the longitudinalsectional view follows the contour. In other words, the sectional viewof FIG. 5 is intended to encompass a variety of annuloplasty rings,planar or otherwise.

The annuloplasty ring 40 includes an inner core 42 forms of therelatively rigid material, such as stainless steel, titanium, or CobaltChromium (CoCr family of alloys: CoCr, L605, MP, MP25, MP35N, Elgiloy,FW-1058). The core 42 provides the “skeleton” of the annuloplasty ring40, and is made of the material that, while it may flex to a certaindegree, resists deformation from the forces experienced once implantedat the valve annulus. The ring core 42 is preferably formed from one ofthe relatively rigid metals or alloys listed above, or even a polymerthat exhibits similar material and mechanical properties. For instance,certain blends of Polyether ether ketone (PEEK) with carbon and an alloymight be used, in which case the core could be injection molded. Anexemplary construction of the ring core 42 is solid titanium or a Tialloy such as Ti-6Al-4V (Titanium-Aluminum-Vanadium), annealed to removeresidual internal stresses, extending from the first free end to thesecond free end.

The term “relatively rigid” refers to the ability of the core 42 toremodel a diseased heart valve annulus without substantial deformation,and implies a minimum elastic strength that enables the ring to maintainits original, or relaxed, shape after implant even though it may flexsomewhat. Indeed, as will be apparent, the ring desirably possesses someflexibility around its periphery. The core 42 cannot function to remodela valve annulus if it is entirely flexible, such as silicone or has athin lateral profile and is made of a highly flexible metal such asNitinol. Such flexible materials and constructions easily deform to theshape of the annulus and therefore will not maintain their originalshape upon implant. In contrast, the present application presentsimprovements to relatively rigid “remodeling” annuloplasty rings.

The ring 40 further includes a suture-permeable interface desirablyhaving one or more layers surrounding or covering the skeletal core 42.For instance, as with many previous annuloplasty rings, an elastomericsleeve 44 and a fabric outer covering 46 surround the core 42. Theelastomeric sleeve 44 may be silicone rubber molded around the core 42,or a similar expedient. The elastomeric sleeve 44 provides bulk to thering for ease of handling and implant, and permits passage of suturesthough not significantly adding to the anchoring function of the outerfabric covering 46. The elastomeric sleeve 44 has a constant wallthickness around a majority of the core 42 of about 0.25 mm, but mayinclude a sewing cuff and is somewhat enlarged at the free ends as willbe described. The fabric covering 46 may be any biocompatible knit orvelour material such as Dacron® (polyethylene terephthalate), anddesirably has a thickness of between 0.33 mm and 0.6 mm.

FIG. 5 shows a plurality of sutures 48 passing through an outer edge ofthe combined elastomeric sleeve 44 and outer covering 46. In a typicalimplant procedure, the sutures 48 are pre-installed at the annulus andbrought out of the body to be threaded through the suture-permeableouter edge of the annuloplasty ring. The surgeon then pushes theannuloplasty ring down the array of sutures until it seats at theannulus. The sutures are then tied off or clipped on the accessible sideof the ring.

As mentioned, the plan view shape of the annuloplasty ring 40 may besuitable for the tricuspid annulus or the mitral annulus. Theillustrated annuloplasty ring 40 is particularly well-suited to beimplanted at and remodel the tricuspid annulus, but if the plan viewshape is modified to a generally rounded D-shape it can also function toremodel the mitral annulus.

As seen in FIG. 5, the illustrated embodiment shows a tricuspid ring 40,with a discontinuous or C-shaped periphery including two free ends 50,52 that define a gap therebetween. As seen in FIG. 5, the inner core 42preferably terminates at two free ends 54, 56 short of the free ends 50,52 of the ring 40. The core 42 is substantially asymmetric and ovoid andwhen implanted the first free end 54 is located adjacent theantero-septal commissure (see FIG. 3). The ring core 42 extends from thefirst free end 54 in a clockwise direction, as seen looking at theinflow side in FIG. 5, around convex segments corresponding to theanterior leaflet, the antero-posterior commissure, the posteriorleaflet, the postero septal commissure, and the septal leaflet withinwhich the second free end 56 terminates. The nomenclature and shapes forthese segments is taken from the standard anatomical nomenclature aroundthe tricuspid annulus as seen in FIG. 3.

It should be further noted that the term “asymmetric” means that thereare no planes of symmetry through the ring core 42 looking from theinflow side, and “ovoid” means generally shaped like an egg with a longaxis and a short axis, and one long end larger than the other. Asmentioned, a substantial portion of the ring core 42 may be planar,though some segments may have up or down bulges or bows.

The exemplary annuloplasty ring 40 features two enlarged regions 58 ofthe elastomeric sleeve 44 having the outer covering 46 thereon at thetwo free ends 50, 52. Preferably, the enlarged regions 58 comprisewidened molded areas of the elastomeric sleeve 44 so as to be highlyflexible or flaccid. Furthermore, a plurality of additional sutures 60are installed at the free ends 50, 52 through the enlarged regions 58.These sutures 60 secure the free ends to the annulus tissue, but becauseof the flaccid nature of the free ends the sutures do not exert a largeamount of pull-through force on the tissue or annuloplasty ring. Thatis, the free ends 50, 52 tend to move with the cyclic nature of theannulus movement such that the assembled components of the ring,sutures, and annulus at the free ends move together. This arrangementgreatly reduces the possibility of dehiscence, especially for tricuspidannuloplasty rings.

FIGS. 5A-5C are lateral sectional views through several locations of theannuloplasty ring of FIG. 5 which illustrate a further aspect ofgradually increase flexibility toward the free ends 50, 52. In oneembodiment, the inner core 42 comprises a series of vertically-orientedbands 62 that are stacked together circumferentially, as seen in FIG. 5Awhich is taken in a midsection of the core. FIG. 5B is taken through asection near the free end 56 of the core 42, and shows how the size andeven number of the bands 62 have been reduced, thus rendering the freeend 56 more flexible than the mid-portion of the core 42. This graduallyincreasing flexibility assists in reducing stresses on the sutures 48and 60, further lessening the chance of dehiscence.

FIGS. 5A and 5B show an outer bulge 64 formed in the elastomeric sleeveon the outer edge of the ring 40. This provides a sewing cufffacilitating passage of suture needles and reducing the chance ofcatching the needle on the assembly of the bands 62. FIG. 5C shows oneform of the enlarged flaccid regions 58 at the free ends 50, 52. Thefree ends 50, 52 are shown as somewhat paddle-shaped with an axialthickness less than the remainder of the ring. However, the free ends50, 52 may also have the same height as the rest of the ring, but justbe wider as shown. Furthermore, though the free ends 50, 52 are shownwith the large region 58 of the elastomeric sleeve 44, the ends maysimply be an extension of the fabric cover 46 without any elastomer. Inother words, the free ends 50, 52 are simply significantly more flexiblethan the regions of the ring 40 having the core 42.

In a preferred embodiment, the enlarged free ends 50, 52 desirably havea circumferential length as measured as an extension from the inner core42 toward the gap in the ring 40 of between about 3-10 mm, though theends could extend in this direction up to 20-25 mm. The radial width ofthe enlarged free ends 50, 52 is also desirable between about 3-10 mm.

FIG. 6 illustrates an alternative annuloplasty ring 80 that isconstructed much like the ring 40 described above, and thus will havesimilar element numbers. Namely, the annuloplasty ring 80 includes aninner skeletal core 42 surrounded by a suture-permeable interface of theelastomeric sleeve 44 and an outer fabric cover 46. The ring 80terminates at two free ends 50, 52, while the inner core 42 terminatesat two free ends 54, 56. As with the earlier embodiments, the two freeends 50, 52 include enlarged regions 82, 84 that provide highly flexibleareas through which to pass additional sutures 86. Once again, theenlarged regions 82, 84 reduce the possibility of dehiscence by movingwith the cyclically moving annulus.

In contrast to the version shown in FIGS. 5-5C, the enlarged regions 82,84 of the free ends 50, 52 of the ring 80 primarily comprise radiallyoutward bulges from the core 42, rather than circumferential projectionsinto the gap between the two free ends. The shape is seen in thelongitudinal section view of FIG. 6, and in the radial cross-section ofFIG. 6C, where the enlarged region 84 comprises a laterally outwardextension of the elastomeric sleeve 44 surrounded by the fabric cover46. Although a portion of the elastomeric sleeve 44 extendscircumferentially beyond the free ends 54, 56 of the core 42 into thegap therebetween, it is nowhere near as large as the earlier embodiment.

FIGS. 6A-6C are lateral sectional views through several locations of theannuloplasty ring 80, illustrating another configuration of core 42.Namely, the core 42 comprises a generally U-shaped channel member 90that may be made of the relatively rigid metal such as titanium. In thisembodiment, the height of the channel member 90 gradually reduces aroundthe ring from the midsection as seen in FIG. 6A until it reaches aminimum at the free ends 54, 56, as seen in FIGS. 6B and 6C. Thisarrangement increases the flexibility of the free ends of the core 42primarily in bending about substantially radial axes. That is, thecross-section of the core 42 remains somewhat stiffer in bending withinthe plane of the ring, and more easily bends up and down.

FIGS. 6A-6C also illustrate an outwardly projecting sewing flange 92formed by the molded elastomeric sleeve 44. Desirably, the sewing flange92 extends around the entire periphery of the ring 80. In an exemplaryembodiment, the radial extent of the enlarged region 84 is between 2-4times as large as the radial extent of the sewing flange 92. That is,the “radial extent” of either the sewing flange 92 when enlarged region84 is that distance projecting outward from the bulk of the elastomericsleeve 44 surrounding the core 42. For example, the radial extent of thesewing flange 92 is given as dimension A, while the radial extent of theenlarged region 84 is given as dimension B. The ratio of B to A isbetween 2:1 to 4:1. In absolute terms, the sewing flange 92 may have adimension A of 1-2 mm, while the dimension B of the enlarged region 84is between 2-8 mm.

FIG. 7 is a longitudinal sectional view of an alternative annuloplastyring 40′ similar to the ring in FIG. 5, and thus will have similarelement numbers. The ring 40′ has enlarged regions 58 of the elastomericsleeve 44 at the two free ends 50, 52 of the ring projectcircumferentially toward each other. However, the gap between the freeends 54, 56 of the core 42 is larger than that in FIG. 5, and is morelike the gap shown in FIG. 6. Because the core free ends 54, 56 arefather apart, the floppy ends 58 are also farther apart. Thisillustrates that the gap between the two free ends 50, 52 can be quitelarge, up to about half the major dimension of the entire ring.

FIGS. 7A-7C show the annuloplasty ring of FIG. 7 in various sections,much like the sections in FIGS. 5A-5C of the earlier ring. One change isthat the floppy ends 58 may be longer than before, so that section 7Bshows a neck portion 94 of the elastomeric sleeve 44 beyond the corefree end 56 and before the enlarged region 58.

FIG. 8 illustrates a still further annuloplasty ring 96 of the presentapplication which again exhibits floppy ends 98 beyond the free ends 54,56 of the core 42. In this embodiment, the floppy ends 98 are notnecessarily radially larger than the remainder of the ring, as shown incross-section in FIG. 8C. The floppy ends 98 may be flattened, as shown,or more cylindrical. The free ends 54, 56 of the core 42 aresignificantly far apart so that the floppy ends 98 extend longer thanpreviously shown. For instance, the floppy ends 98 may extend a distanceL of between about 20-25 mm past the free ends 54, 56 of the core 42.

In addition to providing enlarged floppy ends for the annuloplastyrings, as described above, the free ends may also be secured usingspecialized pledgets. FIG. 9 is a schematic illustration of an exemplaryassembly of an annuloplasty ring 100 and a securing plate 102 forstabilizing the free ends 104, 106 exploded on either side of a valveannulus 110. A tricuspid valve 112 in the annulus 110 is remodeled bythe ring 100. Sutures 114 pass through the highly flexible or floppyfree ends 104, 106 of the ring 100, through the valve annulus 110, andthrough the securing plate 102. Each suture 114 then passes back upwardthrough the securing plate, through the valve annulus, and again throughthe respective free end 104, 106, to be tied off. The presence of thesecuring plate 102 further helps stabilize the floppy free ends 104, 106relative to the annulus 110 without adding rigidity to the structure.Because the securing plate 102 is made of fabric or other flexiblematerial, the free ends 104, 106, and sutures 114 all can move withmovement of the annulus. This greatly reduces the chance of pull out ofthe sutures from the free ends of the ring or from the heart annulustissue.

As with existing rings, rings of the present application are availablein sizes 26 mm through 36 mm in 2 mm increments, having outsidediameters (OD) between 31.2-41.2 mm, and inside diameters (ID) between24.3-34.3 mm. These diameters are taken along the “diametric” linespanning the greatest length across the ring. It should be mentioned,however, that the present invention is not limited to the aforementionedrange of sizes, and rings smaller than 24 mm or larger rings of 38 or 40mm OD are also possible, for example. The “ring size” is the sizelabeled on the annuloplasty ring packaging.

Several typical steps in the implant procedure will be explained. First,the surgeon utilizes valve annulus sizers to measure the tricuspid valvefor annuloplasty ring size. Typical sizing technique for tricuspid valveannuloplasty includes assessment of septal leaflet length using twonotches on a plate-like sizer (such as Tricuspid Sizers available fromEdwards Lifesciences of Irvine, Calif.), and evaluation of anteriorleaflet surface area. The surgeon should not attempt to deform or alterthe ring 40, 80 to conform to a specific annular anatomy, as it coulddamage the ring. Instead, if the ring 40, 80 is not suitably sized forthe annulus, a larger or smaller ring should be selected.

Ultimately, the surgeon determines the proper size of ring, and theassembly of tricuspid annuloplasty ring 40, 80 and a ring holder (notshown) is provided to the operating room. The tricuspid annuloplastyring 40, 80 is supplied in a sterile package with the ring holder. Theprocedure for gaining access to the tricuspid annulus involvesperforming a sternotomy and then stopping the heart and placing thepatient on bypass. The tricuspid annulus is exposed through the rightatrium. Further details on the surgical steps surrounding the tricuspidrepair are well known to the surgeon.

Next, the surgeon or surgeon's assistant attaches a handle to theholder. A plurality of suture needles are passed through the outsideedge of the annuloplasty ring 40, and the additional sutures 60 at thefree ends 50, 52 through the enlarged regions 58. If implanting the ring80 of FIG. 9, the securing plate 102 for stabilizing the free ends 104,106 is placed below the valve annulus 110 and at least two suturespassed down through it. The surgeon uses the needles to pre-install aplurality of implant sutures using horizontal mattress stitches aroundthe annulus, and thread them through corresponding locations around thering 40, 80. No sutures are placed in the atrial tissue or through thearea of the Bundle of His, which may impair cardiac conduction, northrough the right coronary artery. This is a typical implant techniquefor both annuloplasty rings and prosthetic heart valves and is followedby sliding or “parachuting” the ring 40, 80 down the array ofpre-installed sutures into contact with the annulus.

After parachuting the ring 40, 80 down the array of pre-installedsutures into contact with the tricuspid annulus, the implant sutures aretied off using knots or possibly clips (not shown) that eliminate thetime-consuming knot-tying. To increase visibility for this step, thehandle may first be detached from the holder. Finally, when surgeon hassecured the ring 40, 80 to the annulus with the sutures, he/she seversan attachment suture connecting the ring to the holder. Specifically,the surgeon uses a sharp implement such as a scalpel to sever theattachment suture at one or more cutting guides on the holder. Althoughnot show in detail, the attachment sutures pass in and out of the ring40, 80 through a holder template, and tie off at each end to thetemplate. Severing the suture in the middle at the cutting guide permitsthe surgeon to simply pull the holder free from the ring. The attachmentsuture pulls out of the ring 40, 80 at the same time.

Finally, the tricuspid annuloplasty ring 40, 80 is fully implanted atthe tricuspid annulus, with the implant sutures and knots holding it inplace. The annulus is reshaped such that the valve leaflets coapt andprevent regurgitation.

The surgeon and his/her team then evaluates the quality of the repair byventricular pressurization via bulb syringe then transesophagealechocardiography (TEE) after completion of cardiopulmonary bypass. Carein the measurement of the orifice, annuloplasty ring selection, andinsertion technique are essential in achieving a good result. However,associated subvalvular lesions may necessitate additional procedures. Ifcareful application of the annuloplasty ring 40, 80 fails to produceadequate repair of valvular insufficiency as determined byechocardiography, visual inspection, or intraoperative testing, thesurgeon may ultimately remove the ring 40, 80 and replace the diseasedvalve with a prosthetic valve during the same procedure.

While the foregoing is a complete description of the preferredembodiments of the invention, various alternatives, modifications, andequivalents may be used. Moreover, it will be obvious that certain othermodifications may be practiced within the scope of the appended claims.

What is claimed is:
 1. A prosthetic annuloplasty ring, comprising: arelatively rigid ring core defining a discontinuous periphery around anaxis along an inflow-outflow direction with a first free end separatedfrom a second free end across a gap; and a suture-permeable interfacesurrounding the ring core along its length, wherein the interfaceextends circumferentially from both free ends into the gap to formfloppy regions through which sutures may be passed to secure theannuloplasty ring to a valve annulus.